Publisher/Editor: W. D. Cheek, Sr. aka "Dr. Rigormortis”
V2N10: Nov-Dec, 1992
The WORLD SCANNER REPORT “•
A Journal of VHF-UHF Scanner Technology & Engineering ISSN 1061-9240
Published at COMMtronics Engineering; PO Box 262478; San Diego, CA 92196; Copyright (c) 1991-2 <A11 Rights Reserved> $4.oo
CONCLUDING OUR 2nd YEAR!
U.S. ANTI-SCANNER LAW PASSED!
Hard to believe, but this is the 20th issue since V1N1
rolled off the press in January, 1991! Its feature article
was on Subsidiary Carrier Authorization (SCA) for the
PRO-2004/5/6 and other receivers with WFM-mode and
the 88-108 MHz band. Indeed, there are very interesting
signals hidden in the FM Broadcast Band and we
presented the theory of SCA and a method by which to
extract that programming that you're forbidden by law to
monitor without permission from the Broadcasters!
Nothing much has changed since then, except that there's
probably more SCA programming on the air now than
ever. If your interest is up, see the first issue of the WSR
for the gory details of a kit that can be built and installed
in your PRO-2004/5/6 and other WFM receivers to
detect SCA signals. You can purchase this kit from:
FM ATLAS (Bruce Elving)
PO BOX 336; ESKO, MN 55733 (218)879-7676
Bruce Elving regularly publishes and frequently updates
a directory of the FM Broadcast stations of the US,
Canada and parts of Mexico. The FM Atlas is very
detailed, with local maps and triple cross-indexing by
station call letters; frequency and city. Information about
specific station programming, including SCA subcarriers
is also included in the FM Atlas ; a handy reference for
the compleat monitoring shack. Elving also publishes a
periodical newsletter, the FMedia, which lists expired,
new & changed FM license data with regular articles on
the FM market and broadcast technology.
TIME TO RENEW NOW !
Check your mail label now! If there is a florescent pink
slash across the EXPIRE DATE on the label, then this
will be the last issue you will receive unless you renew!
In keeping with tradition established last year, we will be
glad to send you one more issue if budgetary constraints
prevent your renewal before the January, 1992, issue.
You only need write a note of explanation and we'll
extend your subscription for a month. We understand
how the coming Holidays can drain the ol' budget.
Another Freedom is gone!. Not only since 1986 have we
been forbidden to monitor cellular telephone
conversations, but NOW, also forbidden will be scanners
and other radios which are capable of receiving the
cellular telephone bands! Furthermore, and to add insult
to injury, radios that can be "easily modified" to receive
cellular frequencies will also be forbidden by law! I think
this law is to take effect six months after the President
signs the bill, which he is not expected to oppose.
Go figure, then, that by July, 1993, you may not be able
to legally purchase a new PRO-2006, BC-760XLT,
PRO-2022, PRO-2026, BC-800XLT, BC-855XLT.
This might also include the BC-200XLT and PRO-43,
depending on what is meant by "easily modified".
Without question, an entire market array of other radios
may become illegal, almost overnight, to include the
ICOM R-9000, R-7100, R-7000, R-100 and R-l; not to
mention ICOM's line of amateur radios with wideband
receivers! Also to vanish into oblivion will be the
Kenwood RZ-1, Yaesu FRG-9600 and their lines of
amateur radios with wide-band receivers! ACE
Communications may as well go out of business since
most of their scanners are in that law's bullseye.
This law will accomplish little to deter the arts and
sciences of monitoring the cellular bands! Consider that
most 800 MHz scanners, even if not equipped with the
cellular bands, will STILL be capable of receiving
cellular signals by "image frequencies". Say you have
an unmodified PRO-37 and want to listen to 880.000
MHz. No sweat: Perfectly readable image frequencies
of 880 MHz exist at F ±(2)(I.F.) where I.F. is the
receiver's intermediate frequency and F is the frequency
of interest.. The PRO-37's is 10.7 MHz. So, let's figure:
Image 1 = 880.000 MHz + (2)(10.7 MHz)
= 880.000 MHz + 21.4 MHz
= 901.400 MHz, and
Image 2 = 880.000 MHz - (2)(10.7 MHz)
= 880.000 MHz-21.4 MHz
= 858.600 MHz
Take your choice: either of the above two images of 880 MHz are
readily detectable by the PRO-37 (and most other 800 MHz
scanners). The PRO-43 and the PRO-2004/5/6 scanners will not
detect image frequencies by virtue of advanced design with triple
conversion IFs. The PRO-37 and most other scanners sport only
dual conversion IFs. Therefore, the legislative intent of Congress,
in it's infinite wisdom, will be easily defeated by inferior
technology! But this loophole doesn't stop there! A television
receiver with a Ch-14-83 UHF Tuner will readily detect cellular
telephone signals! So, this new law will serve mostly to limit the
resources and technology available to consumer/hobbyists. Might
there be a connection between this new law and the fact that most
people in Congress have cellular telephones? Is there a connection
of this law between the Cellular Industry's high-financed lobby and
hobbyists' lack of one?
Like it's forerunner, the Electronic Communications Privacy Act of
1986, this new law is founded upon gross ignorance and sheer
stupidity. It's based upon a premise not much different than
making it illegal to eavesdrop on nearby, spoken conversations;
like maybe that from an adjacent table in a restaurant! The RF
spectrum differs little from the audio spectrum (they're both just
there) and yet, we're denied the right to monitor portions of it and
the technology to do so is to be crippled with legislation. Oh, and
it doesn't stop there.
I hear that the FBI is seeking the authority and power to cripple the
nation's telephone networks and to invade the privacy of the
nation's telephone communications with legislation for and against
certain technologies and for a capability to interconnect to the
telephone networks right out of their offices!! Apparently, the FBI
wants to be able to connect into the telephone trunks with their
computers and monitoring equipment anytime they want without
the assistance or knowledge of the telephone companies! They
allegedly claim they'll still get a Court Warrant before doing any
actual monitoring! Ha! Now think: for if this is to be, then
telephone technologies have to be legislated or dictated to keep
them nailed down to standards that can be monitored by the FBI.
Kind of like a mandate for a national language so that government
eavesdroppers can understand everything that's said. The FCC has
long mandated "plain language" and standard electronic signals for
the various radio services so that they can monitor the sum and
substance of communications. The FBI wants to do much the same
thing with the nation's telephone networks.
Given the new anti-scanner law, the ECPA of 1986 and the FBI's
efforts to weasel into the telephone system, I have to conclude there
are ample grounds for concern! Seems the government wants to
eavesdrop more and make sure Citizens do it less. To borrow a
slogan: " When guns are outlawed, only outlaws mil have guns ."
1 don't see a hell of a lot we can do about these goings-on other
than to stock up on all the PRO-2004/5/6's that your budget, car
and shack can handle. I don't like to editorialize on this business,
cither, because several years ago, the FCC shut down another
newsletter that I published. The WSR is more fun than the old one
and less controversial, and it would be nice to keep it that way.
But I thought you might like to know what's coming down. Times
arc a'changin', folks.
THE READERS WRITE...
From J.G.. Denver. CO: Dear Doc: Enclosed is my subscription
renewal. $25 is a bargain, considering you saved me that much by
publishing Marymac's low price on the PRO-43. By the way,
Marymac quoted me $169.95 for the new PRO-2026. Where else
can you get 800 MHz and 100 channels at such a price? At the
local hamfest in a year or two...used, maybe.
I would like to see you share this letter with the readers of the
WORLD SCANNER REPORT , lest we techno-junkies get too
involved in computers at the expense of exploring more basic, but
equally powerful ways to use our scanning equipment.
Those readers who have a PRO-2004/5/6, but lack in the computer
department (or, like me, can't hijack the family computer whenever
it suits me), may be interested in a little trick I've learned. With
the PS-90 Search & Store Module from Key Research Co, and a
tape recorder, it is easy to log new frequencies without having to go
the route of a computer interface. The best part is you don't even
have to be in your shack. Now don't get me wrong, I'm not a
down-on-computers type. Computer interfaces will reshape the
scanning hobby, but simple solutions can be satisfying in their own
right, and make good sense.
Set up a LIMIT SEARCH range, say in the military aero band.
Engage the Search & Store Module; fire up the tape recorder on
it's voice activation setting, and go skiing, or take the kids to the
beach for the weekend. When you get home and feel up to it, listen
to the tape and step through the new freqs in the scanner's
The key is in the "BEEP" which happens at the beginning and end
of each search & store cycle. At the end of each transmission,
which will be signaled by that unmistakable "BEEP", pause the
tape recorder and write down the channel number and a few notes
about what you've heard. Then step to the next channel on the
scanner, and resume listening. In this way you not only have a
record of what was heard, but also the frequency. The advantages
of this simple method: (1) you're not tying up the computer for
hours at a time; (2) the new freqs are already in the scamier's
memory; (3) every transmission is saved on tape; and (4) you can
be miles away when a C-130 bellies-in through your backyard.
What more could you ask for (except another vacation)?
Editor's Reply: Why, a scanner/computer interface, of course!
<Grin> Seriously, I'm in tune with ya! By no means do I think
computers are the end of the rainbow. In fact, I am not very
computer-literate, period. But I can a mechanic...an engineer...a
technician...a manager and I'll danged sure make use of any "tool"
that can make my job and/or hobby more fun; better quality; more
productive with less drudgery. But there ARE times when I want
my hands ON the work that’s at hand. See the V2N6 issue, page 7,
of the WSR for a related technique!]
There will always be applications where computers cannot exceed
human creativity and intelligence. Imagine, though, being able to
wield a set of mechanics tools by sheer mind power while you sit
off to one side sipping a cool, frosty or a steaming hot one!
The "WORLD SCANNER REPORT” (c) 1991-2; V2N10: Nov-Dec, 1992; Page 2
Imagine, pumping that floor jack under your car by telekinesis,
and then with no more effort, z//? off a set of lugnuts; change the
tire and go cruising again, all without ever getting a bit of gunk &
grime under your fingernails? Expound upon that thought to
include jerking the engine out from under the hood; giving it a
thorough diagnostic & blueprint; change a piston here; a valve
there; and be off on your way again without ever straining a
muscle or losing a nut or coming up with an extra gasket that, for
the life of you, you don't remember where it was supposed to go.
Well, THAT much remains a head-trip but computers DO offer a
comparable scenario in many, many different situations now! I
began my writing career with pencil & paper; went into hock to
rent a manual typewriter at $10 a month; graduated to a portable
electric typewriter which was absolutely the cat's meow until one
of the keys finally stopped working. Then I sprung for an IBM
Selectric II and went to town! But a couple of years later, it broke
and couldn't be fixed. By that time, my oldest son was studying
computers in high school and talked me into going for broke on an
Apple lie. ComputerLand\ here I come, and walked out with the
Apple, Word Juggler word processor software, dual disk drive and
a printer, all to the tune of $1800 or so. That was eight years ago.
That same Apple He is still in use here with a twin in the kids’
study and there are five more computers doing various things
around here now. Let me venture to submit that in the last three
years, I have written MORE quality material than in the forty
years previous! Not only THAT, but these computers perform the
work that several employees would have been needed to do only a
few years ago. Barely over a year ago, I was proudly proclaiming
that my Apple computers could do anything the IBM’s could do.
Good thing I saw the light and switched rather than fought!
Now I have access to the knowledge of the world via my
computers. I haven't had to run back and forth between home and
library in a year; the WORLD is my library now, right at my
fingertips. The FCC stopped me from communicating via CB
radio several years ago, but now I communicate around the globe
at whim and fancy right from my keyboard. Computers allow me
to do things at a high level of quality that were beyond my reach
without them. I am not a "gamester” nor a computer hobbyist.
Everything I ever learned about the damned things came painfully
and slowly, and STILL does. But I won’t let that obstacle deter me.
You and our dear Readers ought not let obstacles deter you,
either. Henry Ford, Wilbur & Orville Wright and John Glenn ran
into adversity, too. What if they had stopped in their tracks?
But like I said, I’m WITH you. Your approach to analog data
acquisition is exceptionally sound and well worth the knowledge,
skills and minor investment to perform. Tape recorders operate
much more reliably under conditions of emergency power than do
computers. In a major disaster, for instance, like war, earthquake,
hurricane, tornado, etc, computers will be the first to fail. Yet
scanners and tape recorders run very nicely for a long time on
batteries. Computers will never be a substitute for knowing how to
get the job done! That’s like calculators; who doesn’t use one
now? Yet, you really need to know the math you're doing before
the calculator can be of any real assistance. If you don’t know
what you’re doing, a computer will only make things worse. Thank
you for your fine suggestion and time you took to write it up.
SEARCH & STORE MODULES, PRO-2004/5/6
Key Research Co. and their models PS-90 and SS-45 Search &
Store Modules played an important role a few years ago in
launching the Scanner Hacking Revolution. The PS-90 still ranks
up there among the most significant scanner hacks ever to hit the
market! We've discussed the S & S Mods before and I can't
imagine anyone not knowing about them now, but the PS-90 and
SS-45 are still available for the PRO-2004/5/6 from Key Research
Co at PO Box 846-W, Cary, NC 27511-0846. For those not in
the know, the S & S mods are a very effective way to make a
scanner SEARCH for and STORE active frequencies, all without
human intervention. The price is right and installation couldn't be
There are two minor side effects to the S & S Modules, both of
which now have a remedy! It has long been known that the S & S
Modules do not work properly on scanners that have been speeded
up with a crystal to replace the stock resonator. The fix for this
comes in two parts, and if the first one doesn't work, the second
one will. First, add a 1N4148 or 1N914 silicon switching diode in
series with each of the Yellow, Green and Gray wires where they
connect to the scanner's keyboard termination. The cathodes
(banded-ends) of the diodes go toward the S & S Module while the
anodes go to the scanner. Now, if this doesn't work or produce
reliable results, then leave the diodes in place, but add a 100-k
resistor to each of the Brown and Violet wires where they
terminate at the scanner. Solder the two free ends of the resistors
together and then to a nearby ground spot in the scanner! Voila!
The PRO-2004/5 can then be speeded up to roughly 10 MHz
without adverse effects. As far as I know, the PRO-2006 can be
speeded up to 16 MHz without ill effects and for some odd reason,
the S & S modules seem to work quite well on speeded up 2006's
without the above diode & resistor modifications, but keep these
remedies in mind just in case. Now for the great fix!
The Search & Store Modules are susceptible to an annoying effect
caused by the design of the scanner and for which little can be
done outside of my great fix! There is a definite time sequence that
has to elapse during a Search & Store cycle. Try it manually to see
what I mean: as soon as an active frequency is found, press
MONITOR, followed by PROGRAM, ENTER and then SEARCH-
UP or DOWN. If you go too fast, the scanner will ignore one or
more of your keypresses. Now, back to reality: if a static burst or
an atmospheric burp should occur on a frequency encountered
during a SEARCH & STORE sequence whereby the SQUELCH
breaks and sets in something under a tenth of a second, the S & S
function will hang up and seemingly lock. It won't resume
SEARCH until another signal comes in to trigger its completion
sequence. What if that freq is unused in your area and another
signal doesn't come in? The S & S function will stay hung up until
you come along to release it. Well now, it just happens that one of
my slick little (unrelated) mods offers 100% assurance of no hang-
fires in SEARCH & STORE operations! See MOD-29 in Vol-2
of my Scanner Modification Handbook, the Extended Delay!
Also refer to V1N6 and V1N9 for more related material on
Extended Delay and Search & Store.
To get this free "hang-fire" insurance, you need only move the
The "WORLD SCANNER REPORT" (c) 1991-2; V2N10: Nov-Dec, 1992; Page 3
ORANGE wire of the S & S Module from the scanner's IC-3, Pin 3
to the SQ-Out point of the Extended Delay circuit (U-l, Pin 6).
The rest is even easier: start an S & S operation; turn ON the
Extended Delay and set it to about 1/4 to 1/2 second of Delay.
That's it, because even the shortest atmospheric burp to break the
SQuelch will result in the Extended Delay holding the SQuelch
open plenty long enough for the S & S sequence to do its work and
get ready to SEARCH again! There's no liability to this technique,
because if you turn OFF the Extended Delay for any reason, then
the S & S operation will behave exactly as if the Orange wire were
still connected to where Key Research specifies it to go at IC-3, Pin
3. I don't know why you'd want to turn off the Extended Delay
when it works so well, but someone might accidentally flip the
switch, I suppose. But there you have it, the latest good word on
the excellent Search & Store Modules from Key Research.
First, here's the deal on the KeyBoard Extended Function Switch:
it's a way to eliminate the need for external switches on your PRO-
2004/5/6 scanners by pressing TWO KEYS at the same time to
activate or deactivate added circuits & functions. My KeyBoard
Memory Block Selector for the Extended Memory Mods is a
related cousin of the KEFS. Anyway, we found when you press
and hold the scanner’s CLEAR key, that the scanner goes right on
doing whatever it was doing without interruption, BUT any other
keypress at the same time is ignored so long as the CLEAR key is
pressed! How convenient! So the KEFS was evolved to consist of
an AND gate driving a Flip-flop which drives a CMOS Bilateral
Switch, like the common 4066. The KEFS is a simple push-on,
push off type of an electronic switch and is interfaced to the
scanner's Keyboard Connector to take advantage of the keypad
switches. But there is one problem.
FROM CINDY IN "WSR" ADMIN
Dear Readers: I usually stay "behind the scenes" and behind my
desk, but I have to speak out to many of you who knowingly or
otherwise make life more pleasant for me! It's that time of year
again, where many of you are renewing your subscriptions. I want
to offer my thanks to those who have taken some of the drudgery
out of my daily work by cutting off and using the subscription
blank. You see, the reverse side of it has your mailing label which
also contains your identification numbers.
I start work very early in the morning and busy myself all day (and
more times than not, into the night hours) with incoming and
outgoing phone calls, processing in and out mail, receivables and
payables, ordering and obtaining supplies, reviewing monthly
statements, settling problems and/or complaints (just a few of my
laborious duties). Every once in a while, I get a subscription
renewal with the mailing label included, which is VERY MUCH
appreciated! I always try to get your orders and subscriptions filled
and/or shipped within one to three working days, but I have to
confess that those with ID numbers usually go to the top of the
stack, as they go faster and I can get them done in record time.
I also want to personally thank all of you for your patience and
support whether you've been with us since the days of the old
EMTJ or just came on board. It is a pleasure to serve you.
Sincerely, Cindy Cheek; Administrator
EDITOR'S NOTE: Cindy didn't tell you about the other things in
her Job Description Mother, Wife, Organizer, Transporter,
Conniver, Chef, and about a dozen other things. But don’t anybody
get the idea that Cindy is overworked around here. She will get
other things to do in her spare time, maybe after the first of the
year when the rush of subscription renewals settles down a bit.
Maybe a better shudup before I get into trouble? Yes .
A PROMISE KEPT FROM WSR-V1N3
Oops, several people have reminded me that I didn't make good on
a promise of something to come after V1N3. Sure enough, there it
is on page 6, 3rd paragraph where I said I'd show you how to apply
the Keyboard Extended Function Switch to higher current needs.
The "WORLD SCANNER REPORT” (c)
CMOS bilateral switches are really great for low-voltage, low
current, high impedance circuits, to the extent that a single switch
section is limited to 25-ma of current at a voltage not higher than
the supply voltage of the CMOS chip. This really is perfectly great
for many of our switching needs, but the limitations have to be
taken into account. Here's an example: take my Automatic Tape
Recorder Switch (MOD-33) for instance, which is powered by +12
volts and which draws 35-ma or so. No way you can turn this
puppy on and off by means of the KEFS. Or is there?
Sure, it just takes an extra circuit is all and a simple one at that: a
bi-polar transistor switch! Shown below in the first figure is one
complete section of the KEFS as it appeared in V1N3. The next
figure shows what to add to increase the voltage and current
capability of the switch! Nothing out of the ordinary at all!
ADD A TRANSISTOR SWITCH FOR HIGHER CURRENT & VOLTAGE!
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Note in the second figure how there are two places to insert the
circuit to be switched. If your device is installed in the Collector
(A) circuit, then the ground to your device is switched. In that
case, all ground points on your device MUST NOT touch the
scanner's ground anywhere, and instead must all be tied together
before being wired ONLY to the transistor's collector. If your
device is installed in the Emitter (B) circuit, then you're switching
power to your device. Either method can be acceptable, but (B) is
simpler and results in less to worry about. Switched grounds (A)
can get hairy unless you use great care in construction and be sure
that no part of your device is grounded except to the Collector of
the transistor! Now here is how the transistor switch works:
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In order for a bipolar transistor to conduct, its emitter-base junction
must be fonvard biased to about 0.5-volts or more. A point around
0.4-0.5 volts makes the transistor just begin to conduct, but at that
point, it's a current limiter and useless as a switch. The transistor
must be biased close to 0.7 volts for it to be able to pass the desired
current. The purpose of Rb is to set the right bias at the base.
Now, when there is NO positive voltage, or ANY negative voltage
on the base of an NPN transistor, it absolutely will not conduct,
and therefore acts like an open switch. When a positive voltage of
0.5 to 0.7 volts is applied to the base, the transistor will conduct,
thereby acting like a closed switch. If full bias is applied (0.7-v),
then the transistor will conduct maximum current as demanded by
the resistance of your device. Normally, this is not of any major
consideration, but if your switching needs are high current, you
will want to check the characteristics and maximum limits of the
transistor of choice before putting it into your circuit. The
transistor of our example, an NPN type of 2N3904 has a maximum
current limit of 200-ma and a maximum voltage of about 35-v. As
you can see, it is more than adequate for most scanner hack needs.
HB-232 SCANNER/COMPUTER INTERFACE
The Charley Test period has been concluded and the HB-232
Interface is well on its way to carving a new dimension in the
dimensions of scanning. First, here are some statistics. Out of
almost 150 units sold to date, only three requests for refund have
been received. We don't know why, but it's safe to say that one
look at the kit and Manual made them think the job was beyond
their capabilities. A 1.5% return isn't too bad. We had one person
who became VERY frustrated when his HB-232 failed to work,
despite several rounds of suggestions and help. THEN, he came
back, happier than a pig in a dirt pile, when he found that it was
his computer that was at fault and that his HB-232 worked
perfectly. It seems that some of the early Wang computers aren't
quite PC/XT/AT-compatible. Quite a number of others, maybe as
high as 20% or so, have had some sort of problem at initial startup
of the HB-232, but the majority are fully resolved in one or two
rounds of questions & answers. Only a few problems take more
than three go-rounds to resolve and all have been resolved to date.
The neat thing is that 90% of all problems fall into only a few
distinct, easily resolved areas:
1. Interconnecting wiring errors
2. Defective solder joints; errors on the HB-232 Board
3. Failure to follow certain specific instructions:
A. Scanners with speedup crystals won't work with the HB-232
B. Certain wires from HB-232 to scanner cannot exceed 30"
C. Incorrect wiring of the serial input connector
D. Improper Program startup/operation procedures
E. Incompatible computer
4. Defective or improperly setup serial (COM) port
Looking at the second figure, we see where one terminal of the
KEFS CMOS bilateral switch is connected to full time +5v; the
other terminal of this switch connects to the free end of Rb on our
new switch. Thus, when the CMOS switch is open, the base
voltage on the transistor will be zero and the transistor cannot
conduct (Switch Off). When you activate the KEFS to make the
CMOS switch close, then +5 volts is applied to one end of Rb and
then to the base of the transistor. (Switch On). The value of Rb is
not critical, but should be high enough to not let the transistor
conduct much more than you want. A value of 47-k is about right
for switching needs up to 50-ma or so, but you can experiment.
Values as low as 10-k down to 1-k may be required for higher
current needs. As current needs increase, the value of Rb must
decrease to allow the transistor to conduct more. We could go on
with basic transistor theory, but let me refer you to other sources
for more detailed info. There you go; promise from VlN3fulfilled.
The below box depicts a simple analysis of the A & B options:
And these have been the sum and substance of all reported
problems to date. No matter where a problem happens to be, we
are able to direct the User to the location and a quick remedy.
NEW INFO AND A GREAT SOLUTION
Referring to 3.A. above, the HB-232 often would not perform
properly when Wires O-Z exceeded 30" in length. Some users
found problems with lengths of 24". So far, 22" and under seems
to be problem-free, but now we have a fix that allows up to as long
as 4.5-ft. Thanks to the efforts of Larry Jenkins of Hendersonville,
Tennessee, we found that four 100-k resistors, all soldered together
at one end and soldered to a nearby scanner ground and with one
each connected to the scanner's KeyBoard Connector, Pins 9, 10,
11 & 12, where Wires W, X, Y & Z terminate, will eliminate the
problems associated with cable length! The below diagram
illustrates what to do, even if yours doesn't have a problem:
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The "WORLD SCANNER REPORT" (c) 1991-2; V2N10: Nov-Dec, 1992; Page 5
HB-232 PROGRAM VERSION 1.0 ALMOST READY
At long last, the Release vl.O version of the HB-232 control
program is almost ready to go out the door. Until now, everyone
who has purchased an HB-232 Kit is using the Charley 1A
Program which has been thoroughly overhauled and upgraded for
release. We hope to have Release vl.O on the Hertzian Intercept
BBS ready for free downloading by HB-232 Owners on or around
November 11, 1992. If you prefer your program upgrade to be on
disk, please specify which disk size and include $5 S&H with your
order. The HB-232 Release vl.O Program has a host of changes
for the better, including user-configurable color settings; expanded
AutoLogger function; greatly expanded User Tools menu including
a DOS shell; and an evolved and upgraded Script Function. Also,
it is no longer necessary to use the scanner's back panel RESTART
button at program bootup! The HB-232 vl.O is exceptionally
smooth in operation; has plenty of pull-down help screens and lots
of minor improvements over the Charley Test version. By the time
you get this issue, Release vl.O should be ready to ship or
download. Come get yours or order right away.
HB-232 NETWORK EXPANDING!
Host BBS: Hertzian Intercept; (300-16,800-baud), San Diego, CA
(619) 578-9247 (6pm - 1pm)
The Feedhorn BBS (300-9600 baud, 8N1); Los Angeles, CA
(818) 907-7906 (24-hrs)
The Tri-State Data Exchange (300-9600 baud, 8N1); Dubuque, IA
(319) 556-4536 (24-hrs)
HighSierra On-Line (300-9600 baud, 8N1); Lake Tahoe, CA
(916) 577-4438 (24-hrs)
The Red Onion Express (300-14,400 baud, 8N1); Wawayanda, NY
(914) 342-4585 (24-hrs)
D.T.S. BBS (300-2400 baud, 8N1); Dallas, TX
(214) 748-4873 (24-hrs)
The General Alarm BBS (300-2400 baud, 8N1); Indian Springs, CA
(619) 669-0385 (24-hrs)
EVERYONE NOTE: Even though the above BBS's are
networked for the purpose of making the HB-232 Technical
Support Conference as widely available as possible, they also carry
the up and coming RADIOTEK conference which is open to
anyone interested in radio technology and re-engineering. By
checking into any of the above BBS's, you can be in direct contact
with me within 24-hours or less! But I am not the only drawing
card; rather the topic of radio with darned few limits is the prime
attraction. RADIO TEK is a growing public discussion forum
with few rules and maximum encouragement. Also participating
on RADIO_TEK are David Stark, former host of the
SCANNERAMA program on Radio Newyork International; and
Joe Nicholson, a Navy Chief Electronics Technician of many years.
The list of participants is growing and ALL HOBBYISTS are
invited to participate, ask questions or inject comments and
information! People talking to people is the keynote here!
COMPUTER NETWORKING is about people talking to people!
Perhaps this concept is what draws so many of us into radio, but
not all of us are able to communicate by radio, thanks in part to the
FCC's rigorous license requirements and perhaps to the cost of
acquiring the proper equipment. Even so, given the unique
characteristics of radio signals, it is not possible to talk to just
anyone you want, any time you want. Computer networking is
much different; a lot like a "meeting hall" where anyone who
wants can speak, but only one at a time. And yet, hundreds of
speakers can participate just as easily as two. It is something you
have to see to believe, but COMPUTER NETWORKING is
perhaps the very best forum for scannists and shortwave listeners
to meet and interact with one another without regard for political
and geographical boundaries! All you need is a computer, a
modem and a moderate interest in meeting others like yourself!
You wouldn't believe the amount of information and data "out
there" that's available to you through networking! Think about it:
a vast public library of information on your favorite subject right at
your fingertips. So much the better if you favorite subject is
scanners and scanning! Chances are that you are in rare or seldom
contact with very many of your fellow hobbyists; therefore, your
ability to keep up on the latest developments and techniques is
hampered. By networking, however, you can have a solid grip on
the very lifeline of your hobby.
ANTENNA SPLITTERS & SWITCHERS
This subject comes up all the time around hobby radio circles by
virtue of the fact that hobbyists more often than not have to work
under strict limitations of space and budget. The implications are
clear: you may have one scanner and two different antennas; or two
scanners and one antenna, and wish to switch between them for
various situations. There are several permutations and convoluted
ways hobbyists try this sort of thing, and virtually ALL cause some
measure of performance to be degraded.
SIGNAL SPLITTING: The first method, not really a switch, is
to connect one antenna through a "tee" fitting to the inputs of two
different scanners. That way each scanner can run independent of
the other and they'll both pick up signals. Sure do lose a lot of
performance that way. Look at it like this: what happens when
you put a "Y" at the end of your garden hose? Half the original
volume of water goes through each output leg of the "Y". So, too,
does have the signal from one antenna go to each of two scanners
connected on a "tee". Not only THAT, but additional LOSS of
signal is caused by the impedance mismatch of two coaxial cables
connected to one! Add to that an additional loss caused by the
electro-mechanical connections (3) to the "tee". A lot of
performance can be LOST by this improper splitting method.
If you just HAVE to split the feed from one antenna to two
scanners, or in some cases, from one scanner to two antennas,
there is a better way. Use a SPLITTER designed for that purpose,
and the most economical is the cheapo TV-splitter from Radio
Shack, catalog number 15-1141. Your coax cable will have to be
fitted with Type F connectors, but you can use the gold plated
varieties from Radio Shack for minimum losses. This method still
results in 50% of the signal available to each scanner fed by one
antenna, but losses due to mismatch are eliminated. There are
The "WORLD SCANNER REPORT" (c) 1991-2; V2N10: Nov-Dec, 1992; Page 6
commercial models of RF Splitters available for hams & hobbyists
but they are expensive and not always any better. If you want to
look into it more, contact the below company for details about their
complete line of RF connectors, fittings, splitters, switches, coax
cables and more! Please mention that I referred them to you.
PASTERNACK ENTERPRISES; Phone (714) 261-1920
PO BOX 16759; IRVINE, CA 92713
RF & ANTENNA SWITCHERS : By far, it's better to switch
your signals than split 'em. You'll recoup the 3-dB loss (50%) that
goes with splitting. There can be less misc LOSS as well, thanks
to fewer connectors and no mismatches, but there are pitfalls to
avoid when buying or building your own Antenna Switchers!
First, you have to understand the nature of Radio Frequencies (RF)
and especially VHF and UHF frequencies. We've all built cheap
and easy switches for DC and audio/stereo needs and this is fine
for the most part since you can hardly go wrong with direct current
& audio. At VHF-UHF, it's another world, where losses can be
caused by mechanical contacts; unshielded wires and shoddy
construction techniques. It is possible to make relatively loss-free
coaxial cable or antenna switchers, but pretty much out of the
question for the home seamier hobbyist whose interests begin at
about 30 MHz and go all the way up to 1300 MHz or so. Signals
at these frequencies do not behave like DC and audio signals. We
don't have the space to go into all the theory here, but if you can
understand how VHF & UHF signals don't even like coax cable
which is designed to channel RF signals, then you maybe can
understand how these signals don't like to go through switch
contacts, bare wires and unshielded PCB traces! That's the
problem with conventional switches where the signal goes into a
connector on the back of the switch, down through a wire, into and
out of the switch contacts and then back up a bare wire to a another
connector on the rear of the switch. Geeminy snakes, boys & girls,
that's enough potential for loss to gag a small elephant, and much
too much for our palates.
There might be a better way. But first, please understand that it is
BEST to not SPLIT or SWITCH at all. If you must switch your RF
signals, then let's roll our own and do it such a way as to have fun
and come up with something truly unique and useful as hell!
DIODE SWITCHING IS BEST for RF and that's all there is to it!
If we can keep our RF signals from passing through a set of switch
contacts, then we'll overcome a major LOSS point right there!
Diode switching is easy, because when a diode is forward-biased, it
conducts; when not forward-biased, it does not conduct. Sound
familiar? From page 4, this issue, perhaps? Yes, but a diode
switch is simpler than a transistor switch! Not much to it at all,
frankly. Schematically, it is exceptionally simple. The complexity
comes in how you put it together, but it's not all that bad, either.
Construction techniques involve keeping ALL unshielded RF
conductors as short as possible and less than 1” ideally. For
situations where you have to use an unshielded conductor, it is best
to make it on a printed circuit board (flat traces) if you can,
otherwise, you can use solid copper #18 or #20 gauge, pounded out
or pressed into a flat ribbon shape! Flattening a conductor reduces
its inductance! Use light strokes with a hammer to flatten any RF-
carrying copper conductors. Keep the need for length of RF
conductors to 1" or less! How can you do this?
First of all, use a SMALL, die-cast metal box. Radio Shack doesn’t
have any, but most electronic supply houses do. Die-cast metal
boxes are distinguished by thick walls and a very snug, tight-fitting
cover. I bought several at a local surplus firm which measure
about 2"W x 2"L x 1"D; perfect!
Another consideration is to avoid at all costs, sharp bends, kinks
and twists in your RF conductors! Straight and short is the key!
Now let's talk about the best components to use for our VHF-UHF
Antenna Switch. You won't find them at Radio Shack, either! Not
exactly, anyway. The integral parts of our antenna switch are the
switching diodes. And not just ANY diode will do, although if you
want to only be half-serious about this, then the common garden
variety 1N4148 or 1N914 silicon diode can be used. If you take
your scanning on a more serious note, why not go along with the
old saying, "When in Rome, do as the Romans do." Meaning, let's
go for the type of switching diodes like those used in the RF
circuits of the PRO-2004/5/6 scanners: HSR277, a standard
Japanese part number for which I don't know the US cross-
reference, but no matter: these can be ordered from Tandy
National Parts in Ft. Worth, TX: (800) 442-2425. You only need
two, but may as well get a half-dozen or so for good measure. So
when you call, specify you need parts for the PRO-2006, Cat #20-
145, Diodes D3-D8, Part # HSR277. These little puppies are
leadless surface mount diodes, especially designed for fast
switching at ultra-high frequencies. Actually, they do have tiny
tabs of sorts to make soldering a little easier than ordinary SMT
devices. By the way, the green band on these diodes is the cathode.
Next most critical component is the capacitors. Like with the
diodes, not just ANY type will do, though if you are only half
serious, you can use common ceramic disk capacitors. If you take
your scanning seriously, then let's use the same kind as in the
PRO-2006 diode switching circuits: a ceramic 0.001-uF/50-v
surface mount capacitor. May as well order these from Tandy
National Parts when you order your diodes. Again, specify for the
PRO-2006 Cat #20-145, capacitor C-l, Part # RMUMK212B102K.
You might ought to order ten or twelve of these while you're at it.
They're tiny, easy to lose and easy to damage. Spares won't hurt,
and neither the diodes nor the capacitors are all that costly.
Now for the resistors. Same deal; not just any resistor will do,
although if you're half serious and will accept half-results, I
suppose you can use regular leaded resistors. At least get "metal
film" resistors. If you order other parts from Tandy, then order
three each of their 470-k and 1-k SMT resistors, parts #
RCM474J55 and RCM102J55, respectively. Again, specify these
to be for the PRO-2006, resistors R-6 & R-15.
That's it for the critical stuff, I guess. Of course, you should use
high quality BNC chassis-jacks, available from Pasternak
Enterprises, mentioned earlier in this article. Half-decent BNC
jacks are available at Radio Shack. Suit yourself, depending on
how seriously you take your scanning. The rest of the stuff,
including one switch of ANY type, two 220-ohm resistors and a
1.0-uF capacitor are rather generic and non-critical.
The "WORLD SCANNER REPORT" (c) 1991-2; V2N10: Nov-Dec, 1992; Page 7
HOW IT WORKS is uncomplicated and easy to comprehend.
The switch, which can be of any cheapo or desired variety,
switches a DC voltage, +5 to +12 volts, through one or the other of
the 220-ohm resistors and then through the mating 1-k resistor to
the anode of the pertinent diode. A positive voltage on the anode
of a diode with a 470-k resistor at its cathode produces a forward
bias for the diode and thereby allows it to conduct the RF signals
fed to its cathode via the particular antenna. When the switch is
flipped, then that diode becomes unbiased and cannot conduct,
while the other diode becomes forward biased and conducts. You
will see how two diode circuits are used for this switching need,
but you can add a third, a fourth or as many identical diode circuits
as you need for your purposes. The only other change will be the
switch which should have at least as many positions as desired for
the number of antennas to be switched, obviously.
HOW TO BUILD THE ANTENNA SWITCH can be as varied
as the number of people who build it, but there will be a few
common factors: (1) The RF path from either INPUT to the
OUTPUT will be very short. (2) The RF path from either INPUT
to the OUTPUT will be as straight as possible, with no twists,
kinks or sharp bends. (3) The 470-k and 1-k resistors where they
contact the RF paths will not have ANY lead length; i.e., the
bodies of these resistors will be soldered to the RF paths so that
there is no lead-branch from the RF path. (4) The ideal circuit
will be built on a printed circuit board, with the RF paths about an
eighth of an inch wide and with a ground foil running along each
side of the RF path. Other conductors are not important, with
exception of the ground foil which should cover every inch of the
printed circuit board that isn’t needed for something else!
If you don't use a printed circuit board, then build the circuit on
perf board or a flat piece of plastic, perhaps. Build it in the same
fashion as the printed circuit model depicted in this article except
use a dab of super glue to hold the parts in place BEFORE
soldering them later. Do NOT bend leads through holes in the perf
board; make all connections on the same side of the board, which
serves mostly as a foundation for the parts. Use flattened copper
wires for the RF paths and stay as close to the printed circuit
design as possible. If you use leaded resistors, cut all but about a
sixteenth of an inch of lead from the end that solders to the RF
path. The body of the resistor should butt up against the RF trace
or path so that there is no lead branch. Disk capacitors are more
difficult to work with than resistors because it's almost impossible
to not have a lead in the RF path. This is not great, but can be
acceptable if you use very small capacitors with very short lead
lengths. Chip capacitors are best, though, if you can get them.
The 0.001-uF values specified herein are not critical, and the more
common 0.01-uF chip caps can also be used.
WHY THE EMPHASIS ON SPECIAL PARTS ? Well, you can
thrown out the window most everything you ever learned about
Basic Electricity and Electronics, if what you learned or think you
know was accented on DC and low frequency AC. Resistors,
capacitors, inductors, diodes, transistors, and other electronic parts
and conductors only behave the way you were taught when used
with direct current or low frequencies, including audio and RF up
to about 2 MHz to 30 MHz, depending. Above 30 MHz, and it
become a whole new ball game. This isn't because the theory falls
apart; quite the contrary, it holds up, but the tiling is that ordinary
parts don't behave the way you might expect at higher frequencies.
For example, a short length of wire may have an inductance of ten
nano-henries (nH), which is insignificant at DC and low
frequencies. However, at 800 MHz, that 10-nH will present an
impedance of 50-ohms; enough to cause a signal loss of several dB
in the right place at the input to the receiver! Antenna switchers
are always in the "right" place. Leaded electronic components
always have some extra inductance AND capacitance in those
leads, which offer no effect at DC and low frequencies, but at 800
MHz, there are many effects, most of which are uncouth.
You can "get away" with use of conventional components in your
Antenna Switcher if you employ the suggested construction tips &
techniques, but there is always a price to pay for compromise. The
proper components are available through Tandy and other sources
so you may as well use them and not pay the price for compromise
just because it's "easier" or more convenient.
INSTALLAT I ON OF THE ANTENNA SWITCH can be just
about anywhere, including right at the back of your scanner(s).
But there can be one super neat application provided you build the
unit inside a weatherproof enclosure. Suppose you have two
antennas on one mast? There's no real pressing need to run TWO
long lengths of expensive coax from each antenna down to the
back of your scanner! Install the weatherproof Antenna Switch up
on the mast, close to the antennas, and then run just ONE coax
down to the station along with a pair of wires for the DC switching
that's needed! The shield of the downlead coax is ground, so a
cheaper wire pair is less costly and will give your station that
"professional" look and feel!
Otherwise, setup your Antenna Switch anywhere that's convenient
and install the DC switch somewhere even more convenient. Feed
the downleads from each of two antennas to the (A) and (B) inputs
and run a coax patch cable from the (C) output to the back of your
scanner. The other way the Antenna Switch can be used is exactly
backwards, using one antenna to be switched between two (or
more) scanners. In this instance, connect the antenna to the (C)
port and short coax patch cables from the (A) and (B) ports to the
antenna inputs of each scanner. The DC switch can go anywhere.
One very convenient place to install the DC switch is inside the
scanner where it will always be handy. You can get the +5v to
+12v diode bias voltage from the scanner as only a minuscule
amount of current is drawn. If you were into a little more yvork,
you could even install the Antenna Switch board inside the
scanner, too. An extra^NC jack can be installed on the rear of the
scanner to accommodate two antennas. The internal feed from the
stock BNC jack will have to be disconnected and fed to one of the
A-B ports and the C-port fed back to where the stock BNC
connection was cut. Because of this extra level of work, this option
is not for everyone, but I thought I would mention it.
ADVANTAGES OF TWO (or more) ANTENNAS? Most of us
have a favorite slice of the VHF-UHF spectrum. Some people are
into Lo-band VHF; some 800-MHz; some railroads, some aero.
And yet from time to time, we like to sneak a peek at others areas
of the spectrum. It makes perfectly good sense, then, to have one
antenna that's expressly designed for your favored slice of the
spectrum, and yet another for all-round, general purpose needs.
The "WORLD SCANNER REPORT" (c) 1991-2; V2N10: Nov-Dec, 1992; Page 8
LOW-LOSS VHF-UHF ANTENNA SWITCHER
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The "WORLD SCANNER REPORT" (c) 1991-2; V2N10: Nov-Dec, 1992; Page 9
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- to? - I tr
Your basic, casual discone, the most popular of the all-purpose
antennas has no gain, essentially 0-dB or even negative gain,
depending on the band. Discones are not great performers at Lo-
Band VHF, for sure, even those with the extra vertical element.
On the other hand, a simple dipole cut for a specific center
frequency has a gain of 2.2 dB. Other types of omnidirectional
antennas cut for a specific center frequency can have gains between
3 and 6 dB. Yagi and other directional antennas can have gain up
to 10-dB, and if you go all out, 20dB gain is achievable. When a
directional beam antenna is used, there’s all the more reason to
deploy a second omni antenna for general purpose monitoring.
When two or more antennas are used at the monitoring post, the
need for a Switch comes into clear focus. If you change antennas
often, you’ll know what a pain in the butt it is to reach around the
back of a nicely installed scanner to manually swap coax leads! A
simple switch makes life a lot easier.
WHAT IF YOU DON’T WANT TO BUILD YOUR OWN?
Understandable. So either buy a good one, maybe from Pasternak
Enterprises, or get a real cheap one to tide you over while you
think about things. In this case, go for a simple TV-type A-B
switch, like Radio Shack's 15-1249 or 15-1248 and be done with it.
These work about as well for the casual scannist as can be expected
and offer no fuss, no muss and no trouble. For the ’’purist"
however, there can be no substitute for an extremely low loss
antenna system, and our Antenna Switcher this month offers
system flexibilities without a sacrifice of that all-important signal
strength to the receiver.
GOOD & BAD DEALS ON POWER SUPPLIES!
By now, most readers know that we highly recommend operating
scanners (and other radio equipment) from external DC power
supplies rather than straight from the AC wall outlets. You see,
most electronic equipment has a built-in power supply to convert
that high voltage household AC to low voltage DC. This is the
same thing that's done by AC-DC adaptors and other DC power
supplies with an essential difference! An internal power supply
gives off heat INSIDE the radio and adds to the buildup of heat
within. Heat from internal power supplies accounts for up to 95%
of the temperature rise over ambient in electronic equipment. If
your radio is powered from household AC, reach over and feel the
top case after it's been on for a while and you'll see what I mean.
PRO-2004/5/6 scanners are famous for running at temperatures
warm to the touch. Heat accelerates the aging process of most
materials; weakens others and otherwise, does darned little good of
any sort, especially in radios. It's easy, in most cases, to minimize
this aging rate of your equipment. Use an external DC power
supply or adaptor to power your scanners and other radios.
Some scanners are designed solely for external DC power such as
the Uniden BC-760/950XLT. Others are capable of either AC or
DC power. The PRO-2004/5/6 are such examples with a DC jack
on the rear panel. Low end radios that run strictly on AC are easy
to convert. See back issues of the WSR where this approach was
discussed . We recommend complete removal of the AC power
supply from the PRO-2004/5/6 and other scanners so that more
room can be available for modifications and to force exclusive use
of external DC power. Now for the deals, bad and good.
Radio Shack's DC adaptor, 12-v/500-ma (#273-1652B) ain't worth
a hoot. The voltage drops to about 10-volts at 500-ma. Forget this
one, but now comes the good deal! Thanks to Larry Jenkins of
Tennessee who told me about HOSFELT ELECTRONICS, INC;
at 2700 Sunset Blvd; Steubenville, OH 43952; (800) 524-6464.
Hosfelt is a surplus-house with a great 12-v/l-amp DC Adaptor for
$5.98. Order their #56-178. This must be the year for overclaims,
because the above unit isn't good for 1-amp like they say, but I
tested it to 800-ma just fine, and for our scanners at $6 a pop, hell
you can't go wrong! Get Hosfelt's catalog, too! They have about
3,467 other things that you might want, including inexpensive PIN
LINE CONNECTORS for the HB-232 and other projects!
DON’T FORGET TO RENEW SOON!
This is the last issue of 1992!
The "WORLD SCANNER REPORT" (c) 1991-2; V2N10: Nov-Dec, 1992; Page 10
COMMTRONICS ENGINEERING' s
"WORLD SCANNER REPORT"
PO BOX 262478
SAN DIEGO, CA 92196-2478
INTmSJSSUE issn-1 061 -9240 FIRST CLASS MAIL
+ Last Issue of 1992! Renew Soon! Check your Mail Label for a Pink Slash
+ Recollecting Our First Issue; Subsidiary Carrier Authorization Still Hot!
+ US Anti-Scanner Law Passed! Cellular-capable scanners' days are numbered!
+ How to calculate image frequencies; Thanks from Cindy in WSR Admin
+ Reader Explains How to SEARCH & STORE with a tape recorder
+ Update on Key Research SEARCH & STORE Modules; How to overcome their limits!
+ Continued (belatedly) from WSR V1N3\ Using the KEFS for higher current switching needs
+ 1113-232 Scanner/Computer Interface Update; New BBS's; Solutions; Computer Networking
+ Antenna Splitters & Switchers; Make your own Antenna Switch! Explanations & theory
+ Good & bad deals on power supplies; a great source: HOSFELT ELECTRONICS